Seminar by Christian Wagner
Clustering of red blood cells: A model system for soft deformable colloids
The shear thinning of blood results from a reversible disaggregation process of clusters of red blood cells that is induced by the shear forces. These clusters that are known under the name rouleaux and they form only in the presence of the plasma protein fibrinogen or if this is mimicked by some synthetic polymers. The talk will first present experimental techniques that can be used to determine the intercellular adhesion forces, namely optical tweezers and AFM based single cell spectroscopy. The three dimensional shape can be determined by confocal microscopy. Second we will present experimental results on how the RBC clusters are formed in capillary flow. We show that both hydrodynamic and macromolecular induced forces can lead to stable but very different type of clusters. Third we will show that numerical simulations can reproduce these different types of cluster formation and help to sort out the different interaction mechanisms.